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UNCONDITIONAL CONVERGENCE IN THE STRONG OPERATOR TOPOLOGY AND ℓ

Published online by Cambridge University Press:  10 March 2011

IOANA GHENCIU
Affiliation:
University of Wisconsin - River Falls, Department of Mathematics, River Falls, WI 54022-5001 e-mail: ioana.ghenciu@uwrf.edu
PAUL LEWIS
Affiliation:
University of North Texas, Department of Mathematics, Box 311430, Denton, Texas 76203-1430 e-mail: lewis@unt.edu
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Abstract

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In this paper we study non-complemented spaces of operators and the embeddability of ℓ in the spaces of operators L(X, Y), K(X, Y) and Kw*(X*, Y). Results of Bator and Lewis [2, 3] (Bull. Pol. Acad. Sci. Math.50(4) (2002), 413–416; Bull. Pol. Acad. Sci. Math.549(1) (2006), 63–73), Emmanuele [8–10] (J. Funct. Anal.99 (1991), 125–130; Math. Proc. Camb. Phil. Soc.111 (1992), 331–335; Atti. Sem. Mat. Fis. Univ. Modena42(1) (1994), 123–133), Feder [11] (Canad. Math. Bull.25 (1982), 78–81) and Kalton [16] (Math. Ann.208 (1974), 267–278), are generalised. A vector measure result is used to study the complementation of the spaces W(X, Y) and K(X, Y) in the space L(X, Y), as well as the complementation of K(X, Y) in W(X, Y). A fundamental result of Drewnowski [7] (Math. Proc. Camb. Phil. Soc. 108 (1990), 523–526) is used to establish a result for operator-valued measures, from which we obtain as corollaries the Vitali–Hahn–Saks–Nikodym theorem, the Nikodym Boundedness theorem and a Banach space version of the Phillips Lemma.

Keywords

Type
Research Article
Copyright
Copyright © Glasgow Mathematical Journal Trust 2011

References

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